ncurses 6.0 - patch 20170624

ncurses 6.0 - patch 20170624

+ modify c++/etip.h.in to accommodate deprecation of throw() and
  throws() in c++17 (prompted by patch by Romain Geissler).
+ remove some incorrect calls for memory-leaks from 20170617 changes
  (report by Allen Hewes).
+ add test-programs for termattrs and term_attrs.
+ modify _nc_outc_wrapper to use the standard output if the screen was
  not initialized, rather than returning an error.
+ improve checks for low-level terminfo functions when the terminal
  has not been initialized (Redhat #1345963).
+ modify make_hash to allow building with address-sanitizer,
  assuming that --disable-leaks is configured.
+ amend changes for number_format() in 20170506 to avoid undefined
  behavior when shifting (patch by Emanuele Giaquinta).